/[path-sandbox]/trunk/src/sandbox.c
Gentoo

Contents of /trunk/src/sandbox.c

Parent Directory Parent Directory | Revision Log Revision Log


Revision 269 - (show annotations) (download) (as text)
Wed Jul 5 15:01:57 2006 UTC (8 years, 3 months ago) by azarah
File MIME type: text/x-csrc
File size: 17019 byte(s)
Set NOCOLOR to 'no', else ebuild.sh do not set COLS, etc.

1 /*
2 ** Path sandbox for the gentoo linux portage package system, initially
3 ** based on the ROCK Linux Wrapper for getting a list of created files
4 **
5 ** to integrate with bash, bash should have been built like this
6 **
7 ** ./configure --prefix=<prefix> --host=<host> --without-gnu-malloc
8 **
9 ** it's very important that the --enable-static-link option is NOT specified
10 **
11 ** Copyright (C) 2001 Geert Bevin, Uwyn, http://www.uwyn.com
12 ** Distributed under the terms of the GNU General Public License, v2 or later
13 ** Author : Geert Bevin <gbevin@uwyn.com>
14 ** $Header$
15 */
16
17 /* #define _GNU_SOURCE */
18
19 #include <errno.h>
20 #include <signal.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <limits.h>
24 #include <string.h>
25 #include <sys/wait.h>
26 #include <signal.h>
27 #include <unistd.h>
28 #include <fcntl.h>
29
30 #include "sandbox.h"
31
32 struct sandbox_info_t {
33 char sandbox_log[SB_PATH_MAX];
34 char sandbox_debug_log[SB_PATH_MAX];
35 char sandbox_lib[SB_PATH_MAX];
36 char sandbox_rc[SB_PATH_MAX];
37 char work_dir[SB_PATH_MAX];
38 char var_tmp_dir[SB_PATH_MAX];
39 char tmp_dir[SB_PATH_MAX];
40 char *home_dir;
41 } sandbox_info_t;
42
43 static int print_debug = 0;
44
45 volatile static int stop_called = 0;
46 volatile static pid_t child_pid = 0;
47
48 extern char **environ;
49
50 int sandbox_setup(struct sandbox_info_t *sandbox_info)
51 {
52 if (NULL != getenv(ENV_PORTAGE_TMPDIR)) {
53 /* Portage handle setting SANDBOX_WRITE itself. */
54 sandbox_info->work_dir[0] = '\0';
55 } else {
56 if (NULL == getcwd(sandbox_info->work_dir, SB_PATH_MAX)) {
57 perror("sandbox: Failed to get current directory");
58 return -1;
59 }
60 }
61
62 /* Do not resolve symlinks, etc .. libsandbox will handle that. */
63 if (1 != is_dir(VAR_TMPDIR, 1)) {
64 perror("sandbox: Failed to get var_tmp_dir");
65 return -1;
66 }
67 snprintf(sandbox_info->var_tmp_dir, SB_PATH_MAX, "%s", VAR_TMPDIR);
68
69 if (-1 == get_tmp_dir(sandbox_info->tmp_dir)) {
70 perror("sandbox: Failed to get tmp_dir");
71 return -1;
72 }
73 setenv(ENV_TMPDIR, sandbox_info->tmp_dir, 1);
74
75 sandbox_info->home_dir = getenv("HOME");
76 if (!sandbox_info->home_dir) {
77 sandbox_info->home_dir = sandbox_info->tmp_dir;
78 setenv("HOME", sandbox_info->home_dir, 1);
79 }
80
81 /* Generate sandbox lib path */
82 get_sandbox_lib(sandbox_info->sandbox_lib);
83
84 /* Generate sandbox bashrc path */
85 get_sandbox_rc(sandbox_info->sandbox_rc);
86
87 /* Generate sandbox log full path */
88 get_sandbox_log(sandbox_info->sandbox_log);
89 if (1 == exists(sandbox_info->sandbox_log)) {
90 if (-1 == unlink(sandbox_info->sandbox_log)) {
91 perror("sandbox: Could not unlink old log file");
92 return -1;
93 }
94 }
95
96 /* Generate sandbox debug log full path */
97 get_sandbox_debug_log(sandbox_info->sandbox_debug_log);
98 if (1 == exists(sandbox_info->sandbox_debug_log)) {
99 if (-1 == unlink(sandbox_info->sandbox_debug_log)) {
100 perror("sandbox: Could not unlink old debug log file");
101 return -1;
102 }
103 }
104
105 return 0;
106 }
107
108 int print_sandbox_log(char *sandbox_log)
109 {
110 int sandbox_log_file = -1;
111 char *beep_count_env = NULL;
112 int i, color, beep_count = 0;
113 long len = 0;
114 char *buffer = NULL;
115
116 if (1 != is_file(sandbox_log)) {
117 perror("sandbox: Log file is not a regular file");
118 return 0;
119 }
120
121 sandbox_log_file = open(sandbox_log, O_RDONLY);
122 if (-1 == sandbox_log_file) {
123 perror("sandbox: Could not open Log file");
124 return 0;
125 }
126
127 len = file_length(sandbox_log_file);
128 buffer = (char *)malloc((len + 1) * sizeof(char));
129 memset(buffer, 0, len + 1);
130 read(sandbox_log_file, buffer, len);
131 close(sandbox_log_file);
132
133 color = ((is_env_on(ENV_NOCOLOR)) ? 0 : 1);
134
135 EERROR(color,
136 "--------------------------- ACCESS VIOLATION SUMMARY ---------------------------",
137 "\n");
138 EERROR(color, "LOG FILE = \"%s\"", "\n\n", sandbox_log);
139 fprintf(stderr, "%s", buffer);
140 if (NULL != buffer)
141 free(buffer);
142 EERROR(color,
143 "--------------------------------------------------------------------------------",
144 "\n");
145
146 beep_count_env = getenv(ENV_SANDBOX_BEEP);
147 if (beep_count_env)
148 beep_count = atoi(beep_count_env);
149 else
150 beep_count = DEFAULT_BEEP_COUNT;
151
152 for (i = 0; i < beep_count; i++) {
153 fputc('\a', stderr);
154 if (i < beep_count - 1)
155 sleep(1);
156 }
157
158 return 1;
159 }
160
161 void stop(int signum)
162 {
163 if (0 == stop_called) {
164 stop_called = 1;
165 printf("sandbox: Caught signal %d in pid %d\n",
166 signum, getpid());
167 } else {
168 fprintf(stderr,
169 "sandbox: Signal already caught and busy still cleaning up!\n");
170 }
171 }
172
173 void usr1_handler(int signum, siginfo_t *siginfo, void *ucontext)
174 {
175 if (0 == stop_called) {
176 stop_called = 1;
177 printf("sandbox: Caught signal %d in pid %d\n",
178 signum, getpid());
179
180 /* FIXME: This is really bad form, as we should kill the whole process
181 * tree, but currently that is too much work and not worth the
182 * effort. Thus we only kill the calling process and our child
183 * for now.
184 */
185 if (siginfo->si_pid > 0)
186 kill(siginfo->si_pid, SIGKILL);
187 kill(child_pid, SIGKILL);
188 } else {
189 fprintf(stderr,
190 "sandbox: Signal already caught and busy still cleaning up!\n");
191 }
192 }
193
194 int get_sandbox_write_envvar(char *buf, struct sandbox_info_t *sandbox_info)
195 {
196 int retval = 0;
197
198 /* bzero out entire buffer then append trailing 0 */
199 memset(buf, 0, SB_BUF_LEN);
200
201 /* these could go into make.globals later on */
202 retval = snprintf(buf, SB_BUF_LEN,
203 "%s:%s/.gconfd/lock:%s/.bash_history:%s:%s:%s:%s",
204 "/dev/zero:/dev/null:/dev/full:/dev/fd:/proc/self/fd:/dev/pts/:"
205 "/dev/vc/:/dev/pty:/dev/tty:/dev/tts:/dev/console:"
206 "/dev/shm:/dev/shm/ngpt:/var/log/scrollkeeper.log:"
207 "/usr/tmp/conftest:/usr/lib/conftest:"
208 "/usr/lib32/conftest:/usr/lib64/conftest:"
209 "/usr/tmp/cf:/usr/lib/cf:/usr/lib32/cf:/usr/lib64/cf",
210 sandbox_info->home_dir, sandbox_info->home_dir,
211 sandbox_info->work_dir[0] != '\0' ? sandbox_info->work_dir
212 : "",
213 sandbox_info->tmp_dir, sandbox_info->var_tmp_dir,
214 "/tmp/:/var/tmp/");
215 if (SB_BUF_LEN <= retval) {
216 errno = EMSGSIZE;
217 perror("sandbox: Failed to generate SANDBOX_WRITE");
218 return -1;
219 }
220
221 return 0;
222 }
223
224 int get_sandbox_predict_envvar(char *buf, struct sandbox_info_t *sandbox_info)
225 {
226 int retval = 0;
227 /* bzero out entire buffer then append trailing 0 */
228 memset(buf, 0, SB_BUF_LEN);
229
230 /* these should go into make.globals later on */
231 retval = snprintf(buf, SB_BUF_LEN, "%s/.:"
232 "/usr/lib/python2.0/:"
233 "/usr/lib/python2.1/:"
234 "/usr/lib/python2.2/:"
235 "/usr/lib/python2.3/:"
236 "/usr/lib/python2.4/:"
237 "/usr/lib/python2.5/:"
238 "/usr/lib/python3.0/:"
239 "/var/db/aliases.db:"
240 "/var/db/netgroup.db:"
241 "/var/db/netmasks.db:"
242 "/var/db/ethers.db:"
243 "/var/db/rpc.db:"
244 "/var/db/protocols.db:"
245 "/var/db/services.db:"
246 "/var/db/networks.db:"
247 "/var/db/hosts.db:"
248 "/var/db/group.db:"
249 "/var/db/passwd.db",
250 sandbox_info->home_dir);
251 if (SB_BUF_LEN <= retval) {
252 errno = EMSGSIZE;
253 perror("sandbox: Failed to generate SANDBOX_PREDICT");
254 return -1;
255 }
256
257 return 0;
258 }
259
260 int sandbox_setenv(char **env, const char *name, const char *val) {
261 char **tmp_env = env;
262 char *tmp_string = NULL;
263 int retval = 0;
264
265 /* XXX: We add the new variable to the end (no replacing). If this
266 * is changed, we need to fix sandbox_setup_environ() below */
267 while (NULL != *tmp_env)
268 tmp_env++;
269
270 /* strlen(name) + strlen(val) + '=' + '\0' */
271 /* FIXME: Should probably free this at some stage - more neatness than
272 * a real leak that will cause issues. */
273 tmp_string = calloc(strlen(name) + strlen(val) + 2, sizeof(char *));
274 if (NULL == tmp_string) {
275 perror("sandbox: Out of memory (sandbox_setenv)");
276 exit(EXIT_FAILURE);
277 }
278
279 retval = snprintf(tmp_string, strlen(name) + strlen(val) + 2, "%s=%s",
280 name, val);
281 *tmp_env = tmp_string;
282
283 return 0;
284 }
285
286 /* We setup the environment child side only to prevent issues with
287 * setting LD_PRELOAD parent side */
288 char **sandbox_setup_environ(struct sandbox_info_t *sandbox_info, bool interactive)
289 {
290 int env_size = 0;
291 int have_ld_preload = 0;
292
293 char **new_environ;
294 char **env_ptr = environ;
295 char sandbox_write_envvar[SB_BUF_LEN];
296 char sandbox_predict_envvar[SB_BUF_LEN];
297 char *ld_preload_envvar = NULL;
298 char *orig_ld_preload_envvar = NULL;
299 char sb_pid[64];
300
301 /* Unset these, as its easier than replacing when setting up our
302 * new environment below */
303 unsetenv(ENV_SANDBOX_ON);
304 unsetenv(ENV_SANDBOX_PID);
305 unsetenv(ENV_SANDBOX_LIB);
306 unsetenv(ENV_SANDBOX_BASHRC);
307 unsetenv(ENV_SANDBOX_LOG);
308 unsetenv(ENV_SANDBOX_DEBUG_LOG);
309 unsetenv(ENV_SANDBOX_ACTIVE);
310
311 if (NULL != getenv(ENV_LD_PRELOAD)) {
312 have_ld_preload = 1;
313 orig_ld_preload_envvar = getenv(ENV_LD_PRELOAD);
314
315 /* FIXME: Should probably free this at some stage - more neatness
316 * than a real leak that will cause issues. */
317 ld_preload_envvar = calloc(strlen(orig_ld_preload_envvar) +
318 strlen(sandbox_info->sandbox_lib) + 2,
319 sizeof(char *));
320 if (NULL == ld_preload_envvar)
321 return NULL;
322 snprintf(ld_preload_envvar, strlen(orig_ld_preload_envvar) +
323 strlen(sandbox_info->sandbox_lib) + 2, "%s %s",
324 sandbox_info->sandbox_lib, orig_ld_preload_envvar);
325 } else {
326 /* FIXME: Should probably free this at some stage - more neatness
327 * than a real leak that will cause issues. */
328 ld_preload_envvar = gstrndup(sandbox_info->sandbox_lib,
329 strlen(sandbox_info->sandbox_lib));
330 if (NULL == ld_preload_envvar)
331 return NULL;
332 }
333 /* Do not unset this, as strange things might happen */
334 /* unsetenv(ENV_LD_PRELOAD); */
335
336 while (NULL != *env_ptr) {
337 env_size++;
338 env_ptr++;
339 }
340
341 /* FIXME: Should probably free this at some stage - more neatness than
342 * a real leak that will cause issues. */
343 new_environ = calloc((env_size + 15 + 1) * sizeof(char *), sizeof(char *));
344 if (NULL == new_environ)
345 return NULL;
346
347 snprintf(sb_pid, sizeof(sb_pid), "%i", getpid());
348
349 /* First add our new variables to the beginning - this is due to some
350 * weirdness that I cannot remember */
351 sandbox_setenv(new_environ, ENV_SANDBOX_ON, "1");
352 sandbox_setenv(new_environ, ENV_SANDBOX_PID, sb_pid);
353 sandbox_setenv(new_environ, ENV_SANDBOX_LIB, sandbox_info->sandbox_lib);
354 sandbox_setenv(new_environ, ENV_SANDBOX_BASHRC, sandbox_info->sandbox_rc);
355 sandbox_setenv(new_environ, ENV_SANDBOX_LOG, sandbox_info->sandbox_log);
356 sandbox_setenv(new_environ, ENV_SANDBOX_DEBUG_LOG,
357 sandbox_info->sandbox_debug_log);
358 /* Is this an interactive session? */
359 if (interactive)
360 sandbox_setenv(new_environ, ENV_SANDBOX_INTRACTV, "1");
361 /* Just set the these if not already set so that is_env_on() work */
362 if (!getenv(ENV_SANDBOX_VERBOSE))
363 sandbox_setenv(new_environ, ENV_SANDBOX_VERBOSE, "1");
364 if (!getenv(ENV_SANDBOX_DEBUG))
365 sandbox_setenv(new_environ, ENV_SANDBOX_DEBUG, "0");
366 if (!getenv(ENV_NOCOLOR))
367 sandbox_setenv(new_environ, ENV_NOCOLOR, "no");
368 /* If LD_PRELOAD was not set, set it here, else do it below */
369 if (1 != have_ld_preload)
370 sandbox_setenv(new_environ, ENV_LD_PRELOAD, ld_preload_envvar);
371
372 if (!getenv(ENV_SANDBOX_DENY))
373 sandbox_setenv(new_environ, ENV_SANDBOX_DENY, LD_PRELOAD_FILE);
374
375 if (!getenv(ENV_SANDBOX_READ))
376 sandbox_setenv(new_environ, ENV_SANDBOX_READ, "/");
377
378 if (-1 == get_sandbox_write_envvar(sandbox_write_envvar, sandbox_info))
379 return NULL;
380 if (!getenv(ENV_SANDBOX_WRITE))
381 sandbox_setenv(new_environ, ENV_SANDBOX_WRITE, sandbox_write_envvar);
382
383 if (-1 == get_sandbox_predict_envvar(sandbox_predict_envvar, sandbox_info))
384 return NULL;
385 if (!getenv(ENV_SANDBOX_PREDICT))
386 sandbox_setenv(new_environ, ENV_SANDBOX_PREDICT, sandbox_predict_envvar);
387
388 /* Make sure our bashrc gets preference */
389 sandbox_setenv(new_environ, ENV_BASH_ENV, sandbox_info->sandbox_rc);
390
391 /* This one should NEVER be set in ebuilds, as it is the one
392 * private thing libsandbox.so use to test if the sandbox
393 * should be active for this pid, or not.
394 *
395 * azarah (3 Aug 2002)
396 */
397
398 sandbox_setenv(new_environ, ENV_SANDBOX_ACTIVE, SANDBOX_ACTIVE);
399
400 env_size = 0;
401 while (NULL != new_environ[env_size])
402 env_size++;
403
404 /* Now add the rest */
405 env_ptr = environ;
406 while (NULL != *env_ptr) {
407 if ((1 == have_ld_preload) &&
408 (strstr(*env_ptr, LD_PRELOAD_EQ) == *env_ptr))
409 /* If LD_PRELOAD was set, and this is it in the original
410 * environment, replace it with our new copy */
411 /* XXX: The following works as it just add whatever as
412 * the last variable to nev_environ */
413 sandbox_setenv(new_environ, ENV_LD_PRELOAD,
414 ld_preload_envvar);
415 else
416 new_environ[env_size + (env_ptr - environ)] = *env_ptr;
417 env_ptr++;
418 }
419
420 return new_environ;
421 }
422
423 int spawn_shell(char *argv_bash[], char *env[], int debug)
424 {
425 int status = 0;
426 int ret = 0;
427
428 child_pid = fork();
429
430 /* Child's process */
431 if (0 == child_pid) {
432 execve(argv_bash[0], argv_bash, env);
433 return 0;
434 } else if (child_pid < 0) {
435 if (debug)
436 fprintf(stderr, "Process failed to spawn!\n");
437 return 0;
438 }
439 ret = waitpid(child_pid, &status, 0);
440 if ((-1 == ret) || (status > 0)) {
441 if (debug)
442 fprintf(stderr, "Process returned with failed exit status!\n");
443 return 0;
444 }
445
446 return 1;
447 }
448
449 int main(int argc, char **argv)
450 {
451 struct sigaction act_new;
452
453 int i = 0, success = 1;
454 int sandbox_log_presence = 0;
455 long len;
456
457 struct sandbox_info_t sandbox_info;
458
459 char **sandbox_environ;
460 char **argv_bash = NULL;
461
462 char *run_str = "-c";
463
464 /* Only print info if called with no arguments .... */
465 if (argc < 2)
466 print_debug = 1;
467
468 if (print_debug)
469 printf("========================== Gentoo linux path sandbox ===========================\n");
470
471 /* check if a sandbox is already running */
472 if (NULL != getenv(ENV_SANDBOX_ACTIVE)) {
473 fprintf(stderr, "Not launching a new sandbox instance\n");
474 fprintf(stderr, "Another one is already running in this process hierarchy.\n");
475 exit(EXIT_FAILURE);
476 }
477
478 /* determine the location of all the sandbox support files */
479 if (print_debug)
480 printf("Detection of the support files.\n");
481
482 if (-1 == sandbox_setup(&sandbox_info)) {
483 fprintf(stderr, "sandbox: Failed to setup sandbox.");
484 exit(EXIT_FAILURE);
485 }
486
487 /* verify the existance of required files */
488 if (print_debug)
489 printf("Verification of the required files.\n");
490
491 #ifndef SB_HAVE_MULTILIB
492 if (0 >= exists(sandbox_info.sandbox_lib)) {
493 perror("sandbox: Could not open the sandbox library");
494 exit(EXIT_FAILURE);
495 }
496 #endif
497 if (0 >= exists(sandbox_info.sandbox_rc)) {
498 perror("sandbox: Could not open the sandbox rc file");
499 exit(EXIT_FAILURE);
500 }
501
502 /* set up the required environment variables */
503 if (print_debug)
504 printf("Setting up the required environment variables.\n");
505
506 /* Setup the child environment stuff */
507 sandbox_environ = sandbox_setup_environ(&sandbox_info, print_debug);
508 if (NULL == sandbox_environ) {
509 perror("sandbox: Out of memory (environ)");
510 exit(EXIT_FAILURE);
511 }
512
513 /* If not in portage, cd into it work directory */
514 if ('\0' != sandbox_info.work_dir[0])
515 chdir(sandbox_info.work_dir);
516
517 argv_bash = (char **)malloc(6 * sizeof(char *));
518 argv_bash[0] = strdup("/bin/bash");
519 argv_bash[1] = strdup("-rcfile");
520 argv_bash[2] = strdup(sandbox_info.sandbox_rc);
521
522 if (argc < 2)
523 argv_bash[3] = NULL;
524 else
525 argv_bash[3] = strdup(run_str); /* "-c" */
526
527 argv_bash[4] = NULL; /* strdup(run_arg); */
528 argv_bash[5] = NULL;
529
530 if (argc >= 2) {
531 for (i = 1; i < argc; i++) {
532 if (NULL == argv_bash[4])
533 len = 0;
534 else
535 len = strlen(argv_bash[4]);
536
537 argv_bash[4] = (char *)realloc(argv_bash[4],
538 (len + strlen(argv[i]) + 2) * sizeof(char));
539
540 if (0 == len)
541 argv_bash[4][0] = 0;
542 if (1 != i)
543 strcat(argv_bash[4], " ");
544
545 strcat(argv_bash[4], argv[i]);
546 }
547 }
548
549 /* set up the required signal handlers */
550 signal(SIGHUP, &stop);
551 signal(SIGINT, &stop);
552 signal(SIGQUIT, &stop);
553 signal(SIGTERM, &stop);
554 act_new.sa_sigaction = usr1_handler;
555 sigemptyset (&act_new.sa_mask);
556 act_new.sa_flags = SA_SIGINFO | SA_RESTART;
557 sigaction (SIGUSR1, &act_new, NULL);
558
559 /* STARTING PROTECTED ENVIRONMENT */
560 if (print_debug) {
561 printf("The protected environment has been started.\n");
562 printf("--------------------------------------------------------------------------------\n");
563 }
564
565 if (print_debug)
566 printf("Process being started in forked instance.\n");
567
568 /* Start Bash */
569 if (!spawn_shell(argv_bash, sandbox_environ, print_debug))
570 success = 0;
571
572 /* Free bash stuff */
573 for (i = 0; i < 6; i++) {
574 if (argv_bash[i])
575 free(argv_bash[i]);
576 argv_bash[i] = NULL;
577 }
578 if (argv_bash)
579 free(argv_bash);
580 argv_bash = NULL;
581
582 if (print_debug)
583 printf("Cleaning up sandbox process\n");
584
585 if (print_debug) {
586 printf("========================== Gentoo linux path sandbox ===========================\n");
587 printf("The protected environment has been shut down.\n");
588 }
589
590 if (1 == exists(sandbox_info.sandbox_log)) {
591 sandbox_log_presence = 1;
592 print_sandbox_log(sandbox_info.sandbox_log);
593 } else if (print_debug) {
594 printf("--------------------------------------------------------------------------------\n");
595 }
596
597 if ((sandbox_log_presence) || (!success))
598 return 1;
599 else
600 return 0;
601 }
602
603 // vim:noexpandtab noai:cindent ai

Properties

Name Value
svn:eol-style native
svn:keywords Author Date Id Revision

  ViewVC Help
Powered by ViewVC 1.1.20